I recently acquired these stainless steel gratin dishes and I’ve been so excited to use them. I immediately thought of little personal sized shepherds pies when I saw them.
Shepherds pie traditionally uses ground lamb while a cottage pie traditionally uses ground beef. I decided to use ground bison and call this one a Prairie Pie as a special nod to my midwestern roots. Bison is leaner than beef or lamb and has cleaner and mildly earthy taste but is not gamey like venison would be.
For the Filling
1 lb ground bison
Ground lamb or beef also work
1 1/2 cups diced yellow or sweet onion (about half of a large onion)
1 1/2 cups diced fennel (one small bulb)
2 tablespoons olive oil
4 Roma tomatoes, halved lengthwise
2 tablespoons tomato paste
1–2 cups beef or chicken broth, as needed
1 1/2 cups frozen peas
1 teaspoon Italian seasoning
1 teaspoon Worcestershire sauce
2 tablespoons heavy cream
Salt + freshly cracked black pepper, to taste
For the Ricotta-Leek Mash
2 medium yellow potatoes, peeled and cut into 1-inch chunks
1/2 cup chopped leek, thoroughly rinsed
2 tablespoons butter
1/2 cup ricotta
2 tablespoons sour cream
Salt + freshly cracked black pepper, to taste
For Serving
Freshly grated Parmesan
Chopped chives
Instructions
Make the potato topping. Add the peeled and chopped potatoes and leek to a saucepan. Season generously with salt and cover with cold water.
Bring to a boil, then reduce to a gentle boil and cook for about 20–25 minutes, or until the potatoes are very tender and can easily be crushed with the back of a fork.
Drain well, then return the potatoes and leeks to the warm pan. Add the 2 tablespoons butter and mash until mostly smooth.
Add the ricotta and sour cream and continue mashing or whisking gently until creamy and fluffy. Season with salt and pepper to taste, then set aside.
Make the filling. Preheat the oven to 400°F.
Heat a large skillet over medium heat. Add the olive oil, onion, and fennel with a pinch of salt and pepper.
Cook for about 5 minutes, until the vegetables have started to soften.
Add the ground bison and break it into an even layer. Season lightly with salt and pepper, cover, and cook for about 3 minutes.
Stir the bison mixture, then nestle the halved Roma tomatoes cut-side down over the meat.
Cover again and cook over medium-low heat for about 5 minutes, allowing the tomatoes to steam and soften.
Remove the lid. Using tongs, gently peel away the tomato skins; they should come off easily.
Use a potato masher or meat chopper to break down the tomatoes and bison into a chunky, saucy mixture.
Stir in the tomato paste and cook for 1–2 minutes, allowing it to darken slightly.
Add 1 cup broth, Italian seasoning, Worcestershire sauce, and frozen peas.
Cover and cook for about 3 minutes, then stir everything together.
Stir in the heavy cream. Add additional broth, a little at a time, as needed.
You’re looking for the consistency of a thick gravy — saucy and spoonable, but not soupy.
Remove the filling from the heat and let it cool for about 5–10 minutes. This makes it easier to add the potato topping without the two layers blending together.
Transfer the filling to a 9x9-inch baking dish or divide between individual gratin dishes.
Spoon the potato mixture into a gallon-size zip-top bag and snip about 1 cm off one bottom corner.
Pipe the potatoes evenly over the filling. A loose zigzag or wavy pattern gives you lots of little ridges that will brown nicely in the oven.
You can also simply spoon the potatoes over the filling and rough up the surface with a fork.
Bake at 400°F for about 30 minutes, until the filling is bubbling around the edges and the potato topping is beginning to turn golden.
For extra browning, broil for 1–2 minutes at the end, watching closely.
Let rest for 10 minutes before serving.
Finish with freshly grated Parmesan and chopped chives.
Tips
Bison is quite lean, so avoid cooking it aggressively for too long before the casserole goes into the oven. The broth, tomatoes, and cream help keep the filling juicy.
Letting the filling cool slightly before piping on the potatoes helps keep the layers distinct.
If your filling still looks loose before assembling, let it simmer uncovered for a few minutes rather than relying on the oven to thicken it.
For the crispiest potato topping, create plenty of ridges with your piping bag or a fork — those raised edges will brown first.